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Agent-based models (ABMs) stand as an essential paradigm for proposing and validating hypothetical solutions or policies aimed at addressing challenges posed by complex systems and achieving various objectives. This process demands labor-intensive endeavors and multidisciplinary expertise. Large language models (LLMs) encapsulating cross-domain knowledge and programming proficiency could potentially alleviate the difficulty of this process. However, LLMs excel in handling sequential information, making it challenging for analyzing the intricate interactions and nonlinear dynamics inherent in ABMs. Additionally, due to the lack of self-evaluation capability of LLMs, relying solely on LLMs is insufficient to effectively accomplish this process. In this paper, we present SAGE, a general solution-oriented ABM generation framework designed for automatic modeling and generating solutions for targeted problems. Unlike approaches reliant on expert handcrafting or resource-intensive neural network training, SAGE establishes a verifier-assisted iterative in-context learning process employing large language models (LLMs) to leverages their inherent cross-domain knowledge for tackling intricate demands from diverse domain scenarios. In SAGE, we introduce an semi-structured conceptual representation expliciting the intricate structures of ABMs and an objective representation to guide LLMs in modeling scenarios and proposing hypothetical solutions through in-context learning. To ensure the model executability and solution feasibility, SAGE devises a two-level verifier with chain-of-thought prompting tailored to the complex interactions and non-linear dynamics of ABMs, driving the iterative generation optimization. Moreover, we construct an evaluation dataset of solution-oriented ABMs from open sources.It contains practical models across various domains.

Given the escalating intricacy and multifaceted nature of contemporary social systems, manually generating solutions to address pertinent social issues has become a formidable task. In response to this challenge, the rapid development of artificial intelligence has spurred the exploration of computational methodologies aimed at automatically generating solutions. However, current methods for auto-generation of solutions mainly concentrate on local social regulations that pertain to specific scenarios. Here, we report an automatic social operating system (ASOS) designed for general social solution generation, which is built upon agent-based models, enabling both global and local analyses and regulations of social problems across spatial and temporal dimensions. ASOS adopts a hypergraph with extensible social semantics for a comprehensive and structured representation of social dynamics. It also incorporates a generalized protocol for standardized hypergraph operations and a symbolic hybrid framework that delivers interpretable solutions, yielding a balance between regulatory efficacy and function viability. To demonstrate the effectiveness of ASOS, we apply it to the domain of averting extreme events within international oil futures markets. By generating a new trading role supplemented by new mechanisms, ASOS can adeptly discern precarious market conditions and make front-running interventions for non-profit purposes. This study demonstrates that ASOS provides an efficient and systematic approach for generating solutions for enhancing our society.

A playtest is the process in which human testers are recruited to play video games and to reveal software bugs. Manual testing is expensive and time-consuming, especially when there are many mobile games to test and every software version requires for extensive testing before being released. Existing testing frameworks (e.g., Android Monkey) are limited because they adopt no domain knowledge to play games. Learning-based tools (e.g., Wuji) involve a huge amount of training data and computation before testing any game. This paper presents LIT -- our lightweight approach to generalize playtesting tactics from manual testing, and to adopt the generalized tactics to automate game testing. LIT consists of two phases. In Phase I, while a human plays an Android game app G for a short period of time (e.g., eight minutes), \tool records the user's actions (e.g., swipe) and the scene before each action. Based on the collected data, LIT generalizes a set of \emph{context-aware, abstract playtesting tactics} which describe under what circumstances, what actions can be taken to play the game. In Phase II, LIT tests G based on the generalized tactics. Namely, given a randomly generated game scene, LIT searches match for the abstract context of any inferred tactic; if there is a match, LIT customizes the tactic and generates a feasible event to play the game. Our evaluation with nine games shows LIT to outperform two state-of-the-art tools. This implies that by automating playtest, LIT will significantly reduce manual testing and boost the quality of game apps., Comment: 12 pages, 15 figures

Scanning tunneling microscopy (STM) is a widely used technique to study either metallic or semiconducting sample surfaces and electronic structures at the atomic scale. Samples are scanned by a conductive tip whose shape plays an important role in obtaining atomic resolution.My thesis aims to fabricate sharp tungsten tips with a low aspect ratio by using electrochemical etching. To achieve this, the relationship between the aspect ratio and several etching parameters including etching voltage and etchant concentration were studied. To reduce the number of tested etching-parameter combinations we employed the Taguchi method. Additionally, we tried several chemical-etching setup variations and their feasibility. The aspect ratios were then determined with a scanning electron microscope (SEM) and tested in an STM system after the removal of the oxidation layer by either acid treatment or annealing.Our results show that we can successfully fabricate tungsten tips with a low aspect ratio that can enable atomic resolution on standard graphene samples as well as new 2D materials. By employing the standard drop-off etching method we find that the aspect ratio decreases with increasing voltage and etchant concentration. Our measurements also show that the standard drop-off method compared to other etching configurations give the most reliable tips. With this, we can produce tungsten tips with two different thicknesses of wires that can be used for normal STM or in a Qplus sensor configuration.Thus, this thesis will enable the reliable fabrication of tungsten tips in our group for high-resolution STM measurements. In the future, these tips will be used to study two-dimensional materials like Tungsten Ditelluride (WTe2) for their interesting electronic properties.

Tip leakage loss reduction is important for improving the turbine aerodynamic performance. In this paper, the flow field of a transonic high pressure turbine stage with a squealer tip is numerically investigated. The physical mechanism of flow structures inside the cavity that control leakage loss is presented, which is obtained by analyzing the evolution of the flow structures and its influence on the leakage flow rate and momentum at the gap outlet. The impacts of the aerodynamic conditions and geometric parameters, such as blade loading distributions in the tip region, squealer heights, and gap heights, on leakage loss reduction are also discussed. The results show that the scraping vortex generated inside the cavity is the dominant flow structure affecting turbine aerodynamic performance. An aero-labyrinth liked sealing effect is formed by the scraping vortex, which increases the energy dissipation of the leakage flow inside the gap and reduces the equivalent flow area at the gap outlet. The discharge coefficient of the squealer tip is therefore decreased, and the tip leakage loss is reduced accordingly. Variations in the blade loading distribution in the tip region and the squealer geometry change the scraping vortex characteristics, such as the size, intensity, and its position inside the cavity, resulting in a different controlling effect on leakage loss. By reasonable blade tip loading distribution and squealer tip geometry for organizing scraping vortex characteristics, the squealer tip can improve the turbine aerodynamic performance effectively.

Tip leakage loss reduction is important for improving the turbine aerodynamic performance. In this paper, the flow field of a transonic high pressure turbine stage with a squealer tip is numerically investigated. The physical mechanism of flow structures inside the cavity that control leakage loss is presented, which is obtained by analyzing the evolution of the flow structures and its influence on the leakage flow rate and momentum at the gap outlet. The impacts of the aerodynamic conditions and geometric parameters, such as blade loading distributions in the tip region, squealer heights, and gap heights, on leakage loss reduction are also discussed. The results show that the scraping vortex generated inside the cavity is the dominant flow structure affecting turbine aerodynamic performance. An aero-labyrinth liked sealing effect is formed by the scraping vortex, which increases the energy dissipation of the leakage flow inside the gap and reduces the equivalent flow area at the gap outlet. The discharge coefficient of the squealer tip is therefore decreased, and the tip leakage loss is reduced accordingly. Variations in the blade loading distribution in the tip region and the squealer geometry change the scraping vortex characteristics, such as the size, intensity, and its position inside the cavity, resulting in a different controlling effect on leakage loss. By reasonable blade tip loading distribution and squealer tip geometry for organizing scraping vortex characteristics, the squealer tip can improve the turbine aerodynamic performance effectively.

Tip leakage loss reduction is important for improving the turbine aerodynamic performance. In this paper, the flow field of a transonic high pressure turbine stage with a squealer tip is numerically investigated. The physical mechanism of flow structures inside the cavity that control leakage loss is presented, which is obtained by analyzing the evolution of the flow structures and its influence on the leakage flow rate and momentum at the gap outlet. The impacts of the aerodynamic conditions and geometric parameters, such as blade loading distributions in the tip region, squealer heights, and gap heights, on leakage loss reduction are also discussed. The results show that the scraping vortex generated inside the cavity is the dominant flow structure affecting turbine aerodynamic performance. An aero-labyrinth liked sealing effect is formed by the scraping vortex, which increases the energy dissipation of the leakage flow inside the gap and reduces the equivalent flow area at the gap outlet. The discharge coefficient of the squealer tip is therefore decreased, and the tip leakage loss is reduced accordingly. Variations in the blade loading distribution in the tip region and the squealer geometry change the scraping vortex characteristics, such as the size, intensity, and its position inside the cavity, resulting in a different controlling effect on leakage loss. By reasonable blade tip loading distribution and squealer tip geometry for organizing scraping vortex characteristics, the squealer tip can improve the turbine aerodynamic performance effectively.

Tip leakage loss reduction is important for improving the turbine aerodynamic performance. In this paper, the flow field of a transonic high pressure turbine stage with a squealer tip is numerically investigated. The physical mechanism of flow structures inside the cavity that control leakage loss is presented, which is obtained by analyzing the evolution of the flow structures and its influence on the leakage flow rate and momentum at the gap outlet. The impacts of the aerodynamic conditions and geometric parameters, such as blade loading distributions in the tip region, squealer heights, and gap heights, on leakage loss reduction are also discussed. The results show that the scraping vortex generated inside the cavity is the dominant flow structure affecting turbine aerodynamic performance. An aero-labyrinth liked sealing effect is formed by the scraping vortex, which increases the energy dissipation of the leakage flow inside the gap and reduces the equivalent flow area at the gap outlet. The discharge coefficient of the squealer tip is therefore decreased, and the tip leakage loss is reduced accordingly. Variations in the blade loading distribution in the tip region and the squealer geometry change the scraping vortex characteristics, such as the size, intensity, and its position inside the cavity, resulting in a different controlling effect on leakage loss. By reasonable blade tip loading distribution and squealer tip geometry for organizing scraping vortex characteristics, the squealer tip can improve the turbine aerodynamic performance effectively.

Tip leakage loss reduction is important for improving the turbine aerodynamic performance. In this paper, the flow field of a transonic high pressure turbine stage with a squealer tip is numerically investigated. The physical mechanism of flow structures inside the cavity that control leakage loss is presented, which is obtained by analyzing the evolution of the flow structures and its influence on the leakage flow rate and momentum at the gap outlet. The impacts of the aerodynamic conditions and geometric parameters, such as blade loading distributions in the tip region, squealer heights, and gap heights, on leakage loss reduction are also discussed. The results show that the scraping vortex generated inside the cavity is the dominant flow structure affecting turbine aerodynamic performance. An aero-labyrinth liked sealing effect is formed by the scraping vortex, which increases the energy dissipation of the leakage flow inside the gap and reduces the equivalent flow area at the gap outlet. The discharge coefficient of the squealer tip is therefore decreased, and the tip leakage loss is reduced accordingly. Variations in the blade loading distribution in the tip region and the squealer geometry change the scraping vortex characteristics, such as the size, intensity, and its position inside the cavity, resulting in a different controlling effect on leakage loss. By reasonable blade tip loading distribution and squealer tip geometry for organizing scraping vortex characteristics, the squealer tip can improve the turbine aerodynamic performance effectively.

Human BarH-like homeobox 2 (Barx2), a homeodomain factor of the Bar family, has an important role in controlling the expression of cell adhesion molecules and has been reported in an increasing array of tumor types except colorectal cancer (CRC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in CRC. First, we analyzed the expression of Barx2 in two independent public datasets from Oncomine. Subsequently, we evaluated Barx2 mRNA and protein expression by quantitative real-time PCR and western blotting, respectively. It was determined that Barx2 expression was lower in tumor tissues than in adjacent non-tumorous colorectal tissues of CRC patients, consistent with results from the public datasets. Subsequently, a tissue microarray containing 196 CRC specimens was evaluated for Barx2 expression by immunohistochemical staining. It was found that low expression of Barx2 significantly correlated with TNM stage, AJCC stage, differentiation, and relapse in patients with CRC. Patients with lower levels of Barx2 expression showed reduced disease-free survival and overall survival. Furthermore, a trend toward shorter overall survival in the patient group with Barx2-negative tumors independent of advanced AJCC stage and poor differentiation was determined by Kaplan-Meier survival analysis. Based on univariate and multivariate analyses, Barx2 expression was an independent prognostic factor for determining CRC prognosis. Taken together, low Barx2 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC. (C) 2016 The Authors. Published by Elsevier Inc., Funding Agencies|National Natural Science Foundation of China [81272750]

Human BarH-like homeobox 2 (Barx2), a homeodomain factor of the Bar family, has an important role in controlling the expression of cell adhesion molecules and has been reported in an increasing array of tumor types except colorectal cancer (CRC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in CRC. First, we analyzed the expression of Barx2 in two independent public datasets from Oncomine. Subsequently, we evaluated Barx2 mRNA and protein expression by quantitative real-time PCR and western blotting, respectively. It was determined that Barx2 expression was lower in tumor tissues than in adjacent non-tumorous colorectal tissues of CRC patients, consistent with results from the public datasets. Subsequently, a tissue microarray containing 196 CRC specimens was evaluated for Barx2 expression by immunohistochemical staining. It was found that low expression of Barx2 significantly correlated with TNM stage, AJCC stage, differentiation, and relapse in patients with CRC. Patients with lower levels of Barx2 expression showed reduced disease-free survival and overall survival. Furthermore, a trend toward shorter overall survival in the patient group with Barx2-negative tumors independent of advanced AJCC stage and poor differentiation was determined by Kaplan-Meier survival analysis. Based on univariate and multivariate analyses, Barx2 expression was an independent prognostic factor for determining CRC prognosis. Taken together, low Barx2 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC. (C) 2016 The Authors. Published by Elsevier Inc., Funding Agencies|National Natural Science Foundation of China [81272750]

Human BarH-like homeobox 2 (Barx2), a homeodomain factor of the Bar family, has an important role in controlling the expression of cell adhesion molecules and has been reported in an increasing array of tumor types except colorectal cancer (CRC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in CRC. First, we analyzed the expression of Barx2 in two independent public datasets from Oncomine. Subsequently, we evaluated Barx2 mRNA and protein expression by quantitative real-time PCR and western blotting, respectively. It was determined that Barx2 expression was lower in tumor tissues than in adjacent non-tumorous colorectal tissues of CRC patients, consistent with results from the public datasets. Subsequently, a tissue microarray containing 196 CRC specimens was evaluated for Barx2 expression by immunohistochemical staining. It was found that low expression of Barx2 significantly correlated with TNM stage, AJCC stage, differentiation, and relapse in patients with CRC. Patients with lower levels of Barx2 expression showed reduced disease-free survival and overall survival. Furthermore, a trend toward shorter overall survival in the patient group with Barx2-negative tumors independent of advanced AJCC stage and poor differentiation was determined by Kaplan-Meier survival analysis. Based on univariate and multivariate analyses, Barx2 expression was an independent prognostic factor for determining CRC prognosis. Taken together, low Barx2 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC. (C) 2016 The Authors. Published by Elsevier Inc., Funding Agencies|National Natural Science Foundation of China [81272750]

Human BarH-like homeobox 2 (Barx2), a homeodomain factor of the Bar family, has an important role in controlling the expression of cell adhesion molecules and has been reported in an increasing array of tumor types except colorectal cancer (CRC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in CRC. First, we analyzed the expression of Barx2 in two independent public datasets from Oncomine. Subsequently, we evaluated Barx2 mRNA and protein expression by quantitative real-time PCR and western blotting, respectively. It was determined that Barx2 expression was lower in tumor tissues than in adjacent non-tumorous colorectal tissues of CRC patients, consistent with results from the public datasets. Subsequently, a tissue microarray containing 196 CRC specimens was evaluated for Barx2 expression by immunohistochemical staining. It was found that low expression of Barx2 significantly correlated with TNM stage, AJCC stage, differentiation, and relapse in patients with CRC. Patients with lower levels of Barx2 expression showed reduced disease-free survival and overall survival. Furthermore, a trend toward shorter overall survival in the patient group with Barx2-negative tumors independent of advanced AJCC stage and poor differentiation was determined by Kaplan-Meier survival analysis. Based on univariate and multivariate analyses, Barx2 expression was an independent prognostic factor for determining CRC prognosis. Taken together, low Barx2 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC. (C) 2016 The Authors. Published by Elsevier Inc., Funding Agencies|National Natural Science Foundation of China [81272750]

Human BarH-like homeobox 2 (Barx2), a homeodomain factor of the Bar family, has an important role in controlling the expression of cell adhesion molecules and has been reported in an increasing array of tumor types except colorectal cancer (CRC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in CRC. First, we analyzed the expression of Barx2 in two independent public datasets from Oncomine. Subsequently, we evaluated Barx2 mRNA and protein expression by quantitative real-time PCR and western blotting, respectively. It was determined that Barx2 expression was lower in tumor tissues than in adjacent non-tumorous colorectal tissues of CRC patients, consistent with results from the public datasets. Subsequently, a tissue microarray containing 196 CRC specimens was evaluated for Barx2 expression by immunohistochemical staining. It was found that low expression of Barx2 significantly correlated with TNM stage, AJCC stage, differentiation, and relapse in patients with CRC. Patients with lower levels of Barx2 expression showed reduced disease-free survival and overall survival. Furthermore, a trend toward shorter overall survival in the patient group with Barx2-negative tumors independent of advanced AJCC stage and poor differentiation was determined by Kaplan-Meier survival analysis. Based on univariate and multivariate analyses, Barx2 expression was an independent prognostic factor for determining CRC prognosis. Taken together, low Barx2 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC. (C) 2016 The Authors. Published by Elsevier Inc., Funding Agencies|National Natural Science Foundation of China [81272750]